Marshall Strother

Optimizing Radiation Use During Fluoroscopic Procedures: A Quality and Safety Improvement Project

PURPOSE The ionizing radiation used during fluoroscopically guided medical interventions carries risk. The teams performing these procedures seek to minimize those risks while preserving each procedures benefits. This report describes a data-driven optimization strategy. METHODS Manual and automated data capture systems were used to collect a series of different metrics, including fluoroscopy time, kerma area product, and reference point air kerma, from both adult and pediatric interventional radiologic procedures. Tools from statistical process control were used to identify opportunities for improvement and assess which changes led to improvement. RESULTS Initial efforts focused on creating a system capable of reliably capturing fluoroscopy time from all interventional radiologic procedures. Ongoing data analysis and feedback to frontline teams led to the development of a manual workflow that reliably captured fluoroscopy time. Data capture was later supplemented by automatic capture of electronic records. This process exploited the standardized format (DICOM Structured Reporting) that newer fluoroscopy units use to record the radiation metrics. Data analysis found marked differences between the imaging protocols used for adults and children. Revision of the adult protocols led to a stable twofold reduction in average exposure per adult procedure. Analysis of balancing measures found no impact on workflow. CONCLUSIONS A systematic approach to improving radiation use during procedures led to a substantial and sustained reduction in risk with no reduction in benefits. Data were readily captured by both manual and automated processes. Concepts from cognitive psychology and information theory provided a theoretical basis for both data analysis and improvement opportunities.

Magnetic resonance imaging-targeted vs. conventional transrectal ultrasound-guided prostate biopsy: Single-institution, matched cohort comparison

OBJECTIVES To compare magnetic resonance imaging-targeted biopsy (MRITB) and conventional transrectal ultrasound-guided biopsy (TRUSGB) in the detection of prostate cancer (PCa) at our institution. METHODS Our prospective registry of patients undergoing prostate MRITB from December 2010 to July 2013 was analyzed. Patients were matched one-to-one to patients who underwent TRUSGB based on the following characteristics: age, prostate-specific antigen level, prostate volume, race, family history of PCa, initial digital rectal examination (DRE), prior use of 5-alpha reductase inhibitor, and prior diagnosis of PCa. MRITB was performed using a TargetScan system with the patient under general anesthesia. Magnetic resonance imaging suspicious regions (MSRs) were targeted with cognitive registration, and a full TargetScan template biopsy (TSTB) was also performed. RESULTS In total, 34 MRITB patients were matched individually to 34 TRUSGB patients. As compared with TRUSGB, patients who underwent MRITB had a greater overall rate of PCa detection (76% vs. 56%, P = 0.12) and a significantly higher number with Gleason score≥7 (41% vs. 15%, P = 0.03), whereas the rates of Gleason score 6 PCa detection were similar between MRITB and TRUSGB (35% vs. 41%, P = 0.80). As compared with the TSTB, magnetic resonance imaging suspicious regions-directed biopsies during MRITB had a significantly higher overall PCa detection (54% vs. 24%, P<0.01) and Gleason score≥7 PCa detection (25% vs. 8%, P<0.01). When compared with TSTB, TRUSGB had similar detection rates for benign prostate tissue (76% vs. 79%, P = 0.64), Gleason score 6 PCa (16% vs. 14%, P = 0.49), and Gleason score ≥7 PCa detection (8% vs. 7%, P = 1.0). CONCLUSIONS Cognitive registration MRITB significantly improves the detection of Gleason score≥7 PCa as compared with conventional TRUSGB.

RIDE: mixed-mode control for mobile robot teams

There is a growing need for robot control interfaces that allow a single user to effectively control more than one remote robot. The increasing levels of autonomy demonstrated by our robots allow them to be controlled at higher and higher levels of abstraction. However, these systems are not perfect, and human intervention is sometimes required when unexpected circumstances arise, or an object beyond the capability of the perception systems must be analyzed. This requirement for occasional intervention suggests that our interfaces should be capable of both high-level (taskbased) and low-level (direct teleoperation) control of remote robots, with the ability to switch easily between these modes, as required by the situation. The goal of a single operator controlling many robots also suggests that a system that allows an individual to alert the operator when help is needed would be useful. If there are too many robots for the operator to attend to at once, there is a distinct possibility that a robot may sit idle, waiting for help, for a long time without such a notification system.

MP90-15 NONSTEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDS) MAY IMPROVE 30-DAY READMISSION RATES TO THE ED FOR ACUTE EPISODES OF RENAL COLIC

on stone activity is not well studied. Our goal was to determine if SI CaOx correlates with stone activity in calcium oxalate (CaOx) stone formers. METHODS: We reviewed the charts of 604 patients from our stone clinic between 2005 and 2016 and identified CaOx stone formers who had a baseline 24-hour urine collection and at last one follow-up urine collection after the initiation of drug and/or dietary therapy. Patient demographics, imaging studies, serum chemistries, and 24-hour urine studies were recorded in a timeline for each patient. SI was calculated using JESS for each 24-hour urine study. Stone recurrence (SR) was defined as stone growth or new stone formation and no recurrence (NR) indicated no new stone formation. Absolute SI values were compared between times of SR and times of NR, and change in SI from baseline to time of SR were correlated with SI. Statistical analysis was performed with SAS, and significance was set at p<0.05. RESULTS: In total, 255 patients with 358 events were included in the analysis. Mean patient age was 51 13 SD years, with a male:female ratio of 1.3. Comparing NR (98 patients with 97 events) to SR (157 patients with 113) demonstrated no significant difference in mean SI CaOx values (5.6 2.8 versus 5.6 2.9, p1⁄40.6). In addition, in patients who experienced SR (n1⁄4157) no significant difference was seen comparing mean SI CaOx values during NR (n1⁄4148) or SR (n1⁄4113) events (5.9 2.8 versus 5.6 2.9, respectively, p1⁄40.08). For all patients with SR, 65 were identified who experienced both changes from SR to NR (median DSI CaOx 0.20, IQR -1.46-1.21) and NR to SR (median DSI CaOx 0.52, IQR -1.55-1.47). No significant difference was seen (p1⁄40.84). CONCLUSIONS: At first evaluation, neither absolute nor change in SI correlates with stone recurrence and may not be a reliable way to follow effectiveness of medical therapy.

Modified Gleason Grade of Prostatic Adenocarcinomas Detected in the PLCO Cancer Screening Trial

PURPOSE We determined the modified Gleason grade of prostatic adenocarcinomas detected in PLCO to assess grade distribution and compare modified Gleason grades of cancer detected in the intervention arm (organized annual screening) vs the control arm (opportunistic screening). MATERIALS AND METHODS Modified Gleason grading was performed in 859 radical prostatectomy cases by a single urological pathologist. We compared the proportion of cases with high grade disease in the screened arm vs the control arm by logistic regression analysis. RESULTS In the intervention arm a modified Gleason score of 5, 6, 7 (3+4), 7 (4+3), 8, 9 and 10 was assigned in 3.6%, 43.3%, 39%, 7.4%, 3.5%, 3.2% and 0.1% of cases, respectively. In the control arm a modified Gleason score of 5, 6, 7 (3+4), 7 (4+3), 8, 9 and 10 was assigned in 3.0%, 35.7%, 46.4%, 7.1%, 5.4%, 1.9% and 0.5% of cases, respectively, after correcting for high grade disease over sampling. A high grade modified Gleason score of 7 or greater was detected in 53% of cases in the intervention arm vs 61.3% in the control arm after correction (p=0.019). The median modified Gleason score was 7 (3+4) in each arm. CONCLUSIONS A significant percent of cancers in each arm had a component of high grade disease. The modified Gleason grade of prostate cancers detected by organized annual screening was slightly lower than the modified grade of those detected by opportunistic screening. This is an expected consequence of more intensive screening.

In Vivo Evaluation of a Reverse Thermosensitive Polymer for Ureteroscopy with Laser Lithotripsy: Porcine Model

PURPOSE To evaluate the effects of a reverse thermosensitive polymer during ureteroscopy with laser lithotripsy in an in vivo porcine model. MATERIALS AND METHODS Six pigs underwent general anesthesia followed by bilateral ureteroscopy with laser lithotripsy of stone phantoms while measuring intrapelvic renal pressures through bilateral nephrostomy tubes. The procedures were performed in one ureter with the reverse thermosensitive polymer and in the contralateral, control ureter without the reverse thermosensitive polymer. Stone migration lengths, operative times, laser times, laser energy usage, intrapelvic pressures, and postnecropsy histologic examinations of the ureters were compared between the two groups. RESULTS Bilateral ureteroscopy with lithotripsy was successfully performed in five of six pigs. In one pig, only the unilateral control was performed, because the ureter was too narrow to complete the contralateral side. The mean laser time was 12.8 minutes shorter with the use of the reverse thermosensitive polymer group than in the controls (P=0.021). The procedure time, laser energy usage, and retropulsion length was shorter in the reverse thermosensitive polymer group, but did not reach significance. Between the two groups, there was no difference in mean renal pelvic pressures, peak renal pelvic pressures, or postprocedure histologic examinations of the ureters. CONCLUSIONS The use of a reverse thermosensitive polymer during ureteroscopy with lithotripsy may have greater advantages beyond preventing stone retropulsion. Here, the use of a reverse thermosensitive polymer during ureteroscopy with lithotripsy resulted in a significant decrease in laser times. Further clinical investigations could further delineate the advantages of using a reverse thermosensitive polymer during intracorporeal lithotripsy.

RIDE: A Mixed-Mode Control Interface for Mobile Robot Teams

The re is a growing need for robot control interfaces that allow a single user to effe ctively control a large number of mostly-autonomous robots. The ch allenges in controlling such a collection of robots are very similar to the challenges of controlling characters in some genres of video games. In this paper, we argue that interfaces based on elements from computer video games are effe ctive tools for the control of large robot teams. We present RIDE, the Robot Interactive Display Environment, an example of such an interface, and give the results of initial user studies with the interface, which lend support to our claim. Follow this and additional works at: htt p://openscholarship.wustl.edu/cse_research Part of the Computer Engineering Commons, and the Computer Sciences Commons